Iain Duncan-Smith, the Work and Pensions secretary, says that European leaders
told the Prime Minister privately that they backed his bid to block
Jean-Claude Juncker's appointment

David Cameron was privately assured by Germany and Italy that they supported his battle to prevent Jean-Claude Juncker becoming the president of the European Commission, a Cabinet minister has said.

Iain Duncan Smith, the Work and Pensions Secretary, appeared to indicate that Mr Cameron had been told by Angela Merkel, the German chancellor, and Matteo Renzi, the Italian prime minister, that they backed his attempt to block Mr Juncker.

The Prime Minister will this week force a vote on Mr Juncker’s appointment at a Brussels summit.

The move would mark a distinct break from the way that the commission president is usually chosen, with the nomination agreed by consensus between the leaders.

He will on Monday meet Herman Van Rompuy, the head of the European Council, in Downing Street as part of a last-ditch attempt to prevent Mr Juncker getting the job.

Mr Duncan Smith said that if “complacent” EU leaders back Mr Juncker it would be “flicking two fingers” at voters across the continent who have expressed concerns about Brussels.

He also said that Mr Juncker’s appointment would be "very bleak" for Britain's chances of remaining in the EU.

Mr Cameron had been confident because he was told by Angela Merkel, the German Chancellor, and Mr Renzi that they supported his position.

However, in recent days they have decided to endorse Mr Juncker, leaving the Prime Minister furious.

Mr Duncan Smith, a prominent Eurosceptic within the Cabinet, told BBC Radio 5 Live's Pienaar's Politics: "I was talking to the Prime Minister the other day and he said there are a load of countries there who share his view on this, they think this is the wrong man, the Italians were saying it, many were saying it, even privately I understand many Germans say it."

He said that the recent European elections, which saw Eurosceptic parties making huge gains across the continent, show that the EU now needs to be reformed.

Mr Duncan Smith said: “Huge numbers of people said they no longer thought that those who governed them across Europe through the EU actually knew or cared about what they were about or what they wanted with their lives. There was a big, big seismic message to us all across most of the countries and then just to meet together and go on as though nothing has happened

"If they give Jean-Claude Juncker a job, this like literally flicking two fingers at the rest of Europe and saying to all the people out there: we know you voted the way you did but you’re wrong and we’re just going to show you how wrong you are by carrying on as if nothing happened."

Labour has criticised Mr Cameron for “bluster and belligerence” over his handling of Mr Juncker’s bid for the presidency.

Douglas Alexander, the shadow foreign secretary, said: “Even his strongest supporters recognise, that so far the Prime Minister has badly misjudged these vital negotiations, and his public anger appears a very poor substitute for private influence.

“It was not just a bad negotiating approach, but it was bad for Britain for David Cameron to appear to threaten exit from Europe at a key moment of these discussions.”